Quick answer
Onycholysis is the painless separation of the toenail from the nail bed underneath. The lifted portion looks white, yellow, or opaque because air has replaced the normal pink tissue you would see through a healthy attached nail. The most common causes are repetitive trauma (running, hiking, tight shoes), fungal infection, psoriasis, thyroid problems, and certain medications. Once a portion of nail has lifted, it will not reattach. The trigger needs to be removed, the lifted nail trimmed short, and a new nail allowed to grow in over 6 to 12 months.
What it is
A healthy toenail is firmly attached to the nail bed (the soft pink tissue underneath) along most of its length, with only the tip free. In onycholysis, that attachment fails and a portion of the nail lifts away from the bed. The space underneath fills with air, debris, and (often) microbes — which is why the lifted area looks pale and is vulnerable to secondary fungal infection.
The separation usually starts at the distal (front) edge of the nail and progresses backward toward the cuticle. Sometimes it starts on one side and works across.
Causes
- Repetitive trauma — running, hiking downhill, dancing, kicking sports, ill-fitting shoes that allow the foot to slide forward and impact the nail edge with each step
- Fungal infection (onychomycosis) — the leading non-traumatic cause; the fungus disrupts the bond between nail and bed
- Psoriasis — both nail psoriasis directly and the inflammation around psoriatic skin can drive separation; nail pitting often accompanies
- Thyroid disease (especially hyperthyroidism, called “Plummer’s nails”)
- Iron-deficiency anemia
- Certain medications — tetracyclines (with sun exposure, called photo-onycholysis), some chemotherapy drugs, retinoids, fluoroquinolones
- Chemical exposure — frequent contact with cleaning solutions, solvents, harsh nail products
- Allergic contact reaction to nail cosmetics (gel polish, acrylic glue, nail hardener)
- Aggressive manicures that push the cuticle back too far or clean too deep under the nail
Symptoms
- A portion of the nail looks white, yellow, or opaque instead of the normal pink translucent appearance
- The lifted area can be lifted further with gentle pressure (do not actually do this)
- Usually painless unless infection develops
- Debris can accumulate under the nail
- Discoloration over time as the lifted area picks up environmental staining or fungal pigments
If pain, pus, redness, or fever develops, the area has likely become secondarily infected.
Diagnosis
- History and exam — looking for triggers (footwear, sport, recent illness, new medication, manicure routine)
- Nail clipping for microscopy and culture — the most useful test if fungus is suspected (the lifted area is a perfect environment for it)
- Skin exam — looking for psoriasis elsewhere on the body, eczema, or other systemic clues
- Blood tests — sometimes ordered for thyroid function or iron status if the cause is not clear
Treatment
The two-part rule: remove the trigger + let the nail grow out.
Trim the lifted portion
Cut the loose nail back to where it is firmly attached. This removes the dark moist space where fungus thrives, and reduces the leverage that drives further separation. Trim conservatively — do not cut into attached nail.
Address the underlying cause
- Trauma — better-fitting shoes (toe box width and length), tight lacing on downhills, addressing related conditions like bunions or hammertoes that change foot mechanics
- Fungal infection — topical antifungal nail solution (efinaconazole, ciclopirox) or oral antifungal (terbinafine) for confirmed cases. See toenail fungus for the full hierarchy.
- Psoriasis — topical corticosteroid or vitamin D analog at the cuticle; systemic therapy if widespread psoriasis
- Medication-related — discuss with the prescribing clinician whether the medication can be changed
- Manicure-related — stop gel/acrylic, switch to plain polish or none, remove polish with acetone-free remover
Keep the area clean and dry
- Wash the foot daily and dry thoroughly
- Avoid soaking the foot in long baths
- Wear breathable shoes and moisture-wicking socks
- Antifungal foot powder in shoes can help prevent secondary fungal colonization
Time
Toenails grow about 1 to 2 millimeters per month. A new nail growing from the base will take 6 to 12 months to fully replace the affected nail. There is no shortcut.
When to see a clinician
- The lifted area is spreading despite removing obvious triggers
- Pain, pus, redness, or fever suggesting infection
- Pigment changes that do not look right for trauma or fungus (could indicate melanoma — see skin lesions)
- Multiple nails affected without obvious cause (suggests systemic cause)
- Diabetes or peripheral arterial disease, where any nail problem deserves prompt evaluation
- The nail is being lost entirely
Bottom line
Onycholysis is the painless separation of the toenail from the bed. Most cases are from repetitive shoe trauma, fungal infection, or skin conditions like psoriasis. The lifted portion will not reattach; the affected nail must grow out over 6 to 12 months while the underlying cause is addressed. The single most useful step is identifying and removing the trigger — better shoes, treating fungus, or stopping the offending nail product.
Frequently asked questions
Why is my toenail lifting off my skin?
The most common reasons are repetitive trauma (running, hiking, ill-fitting shoes), fungal infection, psoriasis of the nail, thyroid disease, and certain medications (some chemotherapy drugs, tetracycline antibiotics taken with sun exposure). Often it is not painful, but the lifted area collects debris and is more vulnerable to fungal colonization, which is why early treatment matters.
Will my toenail reattach?
Sometimes yes, sometimes no. Once a toenail has lifted from the bed, that specific portion will not reattach. The nail must grow out and a new healthy nail grows in behind it from the matrix at the base. This typically takes 6 to 12 months for a toenail. Removing the trigger (better shoes, treating fungus, stopping the offending medication) prevents new lifting and gives the new nail a chance to attach normally.
Is onycholysis the same as toenail fungus?
No, but fungus is a common cause of onycholysis. Onycholysis just means the nail has separated from the bed; the cause can be trauma, fungus, psoriasis, thyroid problems, or chemicals. Fungal onycholysis specifically also has yellow, white, or brown discoloration, thickening, and crumbling debris. A clinician can take a clipping or scraping for microscopy and culture to confirm whether fungus is involved.
How do I treat onycholysis at home?
Trim the lifted portion of the nail back to where it attaches, keep the area clean and dry, and avoid manicures or harsh nail products. Wear roomy shoes. If you suspect fungus, an over-the-counter antifungal nail solution can help. The new nail growing in from the base needs about 6 to 12 months to fully replace the affected nail. If it spreads, becomes painful, or develops pus, see a clinician.
Can I still paint my nails if I have onycholysis?
Better not, especially with gel or acrylic. Nail polishes and adhesives often contain chemicals that worsen the separation, and gel/acrylic procedures use UV exposure that can drive further lifting. Let the nail recover plain. If you must polish for an event, use a simple breathable polish and remove it with an acetone-free remover.
Sources
Last updated: May 3, 2026
About the author
Written and reviewed by a Doctor of Podiatric Medicine (DPM) practicing in Arizona for 6+ years. Board-certified by the American Board of Podiatric Medicine (ABPM); graduate of Midwestern University Arizona College of Podiatric Medicine.
Last clinically reviewed: May 3, 2026